Jonsered BC 2228 - Component maintenance and adjustment; Adjusting start throttle speed

aWARNING: The cutting attachment may be
spinning during carburetor adjustments. Wear
your protective equipment and observe all safety
instructions. Be sure the cutting attachment stops
turning when the engine idles. When the unit is
turned off, make sure the cutting attachment has
stopped before the unit is set down.
CAUTION: If the cutting attachment rotates
when the engine is idling the idle adjustment
screw T should be turned counterclockwise until
the cutting attachment stops.
Recommended idle speed:
See “Technical data” section.
Recommended max. speed:
See “Technical data” section.
 Fine adjustment of the idle speed-T
Adjust the idle speed using the idle adjustment
screw-T if it is necessary to readjust. First, turn the
idle adjustment screw-T clockwise until the cutting
attachment starts to rotate. Then, turn the screw
counterclockwise until the cutting attachment stops.
The idle speed is correctly adjusted when the engine
will run smoothly in every position. The idle speed
should also be well below the speed at which the
cutting attachment starts to rotate.
 Adjusting the start throttle speed
The correct start throttle speed is set by means of an
adjuster on the rear of the handle next to the cable.
Use this screw (4 mm Allen screw) to increase or
decrease the start throttle speed.
Proceed as follows:
1. Run the machine at idle.
2. Press the start throttle lock as described under the
heading Starting and stopping.
3. If the start throttle speed is too low (below 4000
rpm), turn adjuster screw (A) clockwise until the
cutting attachment starts to rotate. Then turn
adjuster screw (A) clockwise an additional 1/2 turn.
4. If the start throttle speed is too high, turn adjuster
screw (A) counterclockwise until the cutting
attachment stops. Then turn adjuster screw (A)
clockwise an additional 1/2 turn.
aWARNING: If the idle speed cannot be
adjusted so that the cutting attachment stops,
contact your servicing dealer. Do not use the
machine until it has been correctly adjusted or
repaired.
Mufer
NOTE: Mufer is tted with a catalytic converter
designed to reduce exhaust gases.
(Starter housing removed for clarity)
The mufer is designed to reduce the noise level and
to direct the exhaust gases away from the operator.
The exhaust gases are hot and can contain sparks,
which may cause re if directed against dry and
combustible material.
Mufers are equipped with a special spark arrestor
mesh. The mesh should be checked and, if necessary,
cleaned by a servicing dealer. If the mesh is damaged,
it should be replaced.
If the mesh is frequently blocked, this can be a sign
that the performance of the catalytic converter is
impaired. Contact your servicing dealer to inspect
the mufer. A blocked mesh will cause the machine
to overheat and result in damage to the cylinder and
piston.
(Starter housing removed for clarity)
CAUTION: Never use a machine that has a faulty
or loose mufer. Ensure the mufer bolts are tight.
aWARNING: Mufers tted with catalytic
converters get very hot during use and remain so
for some time after stopping. This also applies at
idle speed. Contact can result in burns to the skin.
Remember the risk of re!
aWARNING: The inside of the mufer contain
chemicals that may be carcinogenic. Avoid
contact with these elements in the event of a
damaged mufer.
aWARNING: Engine exhaust fumes contain
carbon monoxide, which can cause carbon
monoxide poisoning. Do not start or run the
machine indoors, or anywhere that is poorly
ventilated.
The exhaust fumes from the engine are hot and
may contain sparks which can start a re. Never
start the machine indoors or near combustible
material!
Spark plug
The spark plug condition is inuenced by:
● incorrect carburetor adjustment.
● an incorrect fuel mixture (too much or incorrect type
of oil).
● a dirty air lter.
These factors cause deposits on the spark plug
electrodes, which may result in operating problems
and starting difculties.
If the machine is low on power, difcult to start or runs
poorly at idle speed always check the spark plug rst
before taking any further action.
If the spark plug is dirty, clean it and check that the
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